In our lives, mixers such as soymilk makers, coffee machines, sand ice makers and the like, which are commonly used as home electrical appliances, are extensively used to mix and smash various food, so as to make increasing delicious food in various styles.
The motors in the existing mixers release high level of heat when the mixers are working, due to high rotation speed of the motors. Therefore, fans are mounted on the end of the rotation axes of the motors to release the heat out of the motors, thereby avoiding the damage of the motors due to overheat and allowing the motors to stably and normally operate.
However, such heat dissipation structure has the following shortcomings:
1. The operation of the fan and the motor will be stopped at the same time, while the internal temperature of the motor is still very high at this time. Thus, the internal coils of the motor will be easily damaged, and the service life of the motor will be reduced.
2. The fan is synchronously rotated with the motor at the same speed as the motor. When the motor is rotated at high speed, the vibration and the high level of noise up to 85 to 100 db will be generated in the fan, and thus the fan will be worn down in an expedited way, thereby producing an influence on the service life of the fan and reducing the performance of the product.